This invention concerns a sealing cap for vacuum containers. Particularly, this invention is directed to a vacuum container having an elastic sucking plate that is repeatedly pressed down to pump out air from a container, which will be evacuated without using an air pump.
There is a known conventional vacuum container shown in FIG. 6 including a container 1, a cap 11, a stop valve 12, and a leak valve 13 provided on the cap 11. An air pump 14 is placed on the cap for pumping out the air from the container 1 when it is desired to preserve food stored in the container for a long period of time.
However, this conventional vacuum container has disadvantages in practical use as follows:
1. The air pump and the container are independent units, so that when the container is to store food and is to be pumped out, the air pump has to be found. If the air pump should be lost, the container becomes a common one, unable to preserve food in a vacuum.
2. The air pump has to be placed just on the stop valve of the cap, and must be pulled up and pushed downwith a comparatively large force. During the pumping operation the air pump may sway, and even worse, may separate from the stop valve. Then, the air pump must be repositioned. Additionally, the pumping capacity of the air pump is limited, with pulling and pushing force required being larger and larger as the degree of vacuum within the container becomes greater.
3. The leak valve consists of a small stopper and a leak hole for receiving the stopper therein. That arrangement is not convenient nor practical to use, and the stopper is likely to drop off.